Some photoelectric conversion devices include a light absorbing layer comprised of a chalcopyrite-based Group I-III-VI compound semiconductor such as CIGS. Japanese Patent Application Laid-Open No. 2000-156517 describes an example where a light absorbing layer comprised of a thin film of a compound semiconductor such as Cu(In,Ga)Se2 is located on an electrode formed on a substrate. Located on this light absorbing layer are a buffer layer comprised of CdS and a transparent conductive film comprised of ITO.
In this photoelectric conversion device, a vacancy generated in part of a chalcopyrite structure may lead to a defect. If such a defect is generated in the light absorbing layer, it becomes hard to extract a large current from the light absorbing layer.